AMERICAN COLEOPTERA. 209 



The thorax is less transverse thaa the preceding species. The im- 

 pression at the anterior margin contains a puncture. 



I. nigrellu8, Leo. New Species, p. 59. — Black, shining. Head finely alutace- 

 0119, vertex bifoveato and with a few piinotures. Thorax longer than wide oval, 

 apex truncate, base narrow rounded; sides moderately rounded narrowing 

 only at basal third; apical margin on each side impressed, impression limited 

 externally by a slight carina ; disc on each side slightly longitudinally con- 

 cave, middle slightly less concave and with the median line finely marked ; 

 surface slightly, more opaque than the elytra, finely alutaceous and very 

 sparsely punctulate. Elytra longer than wide, finely alutaceous, sparsely 

 punctulate, sutural stria entire. Abdomen very finely alutaceous, and with 

 fine punctures as in /M.scia<M5. Legs piceous, knees and apices of tibire paler. 

 Length .10 inch ; 2.5 mm. 



In this the thorax attains its greatest length, among our species. 



Occurs in the Sacramento Valley south, under oak bark. 



I. canadensis, n. sp. — Piceous shining, abdomen nearly black. Head aluta. 

 ceous, vertex, bifoveate and punctured. Thorax oval as broad at apex as long, 

 flat, finely alutaceous, sparsely punctulate, median line scarcely distinct: apex 

 with slight injpression on each side limited externally by a slight elevation; 

 anterior angles obtusely rounded, .sides broadly rounded and gradually narrow- 

 ing to apex. Elytra one-fourth longer than wide, surface nearly smooth very 

 indistinctly alutaceous and finely punctulate; sutural stria distinct and entire ; 

 color slightly paler than thorax. Abdomen very finely alutaceous, each seg- 

 ment with four punctures nearer the anterior margin. Body beneath colored 

 as above. Length .10 inch; 2.5 mm. 



A single .specimen sent me among a number of other species in 

 alcohol by 3Ir. Johnson Pottit, of trrimsby Ontario. 



The species of this genus are all referred to Elntsh, Cast., Gem- 

 mingerand Harold, Catalogus, p. 675, which has priority over fso- 

 intt/us. VjV.. by five years and should be adopted, the name homa/ua be- 

 ing used in the present instance for convenience. 



Descriptions of New Speoies of ELATERIDiE, of the United States. 

 BY (iEO. II. HORN, M. D. 



MERISTHTJ8, Candeze. 

 M. cristatus, n. sp. pi. IV, fig„ 2. — Pale testaceous. Head moderately con- 

 vex rather densely clothed with whitish scales, vertex very slightly impressed. 

 Antennfe testaceous, second joint one-half longer than the third, last joint 

 large obliquely emarginate at apex. Thorax longer tiran broad gradually nar- 

 rower in front, sides moderately rounded, slightly sinuate behind, hind angles 

 nearly rectangular, anterior angles acute, disc of thorax convex.'with transverse 

 basal impression, and flattened in the region of the hinder angles, median line 

 impressed, surface with sparsely placed whitish scales lateral margin distinctly 

 crenulate. Scutellum oval with a strong crest along its middle. Elytra 

 moderately convex, as wide as the thorax, with shallow strice, intervals finely 

 tuberculate, each tubercle bearing a whitish scale. Body beneath with whitish 



